Various flagging or marking devices have been developed for indicating the location of an object at the side of a highway or roadway in order to enhance the visibility of the object or otherwise alert drivers on the highway of its position. There is a particular need for such devices where adverse weather conditions are encountered, such as where relatively large amounts of snow have accumulated at the side of the highway or the visibility of the object is otherwise reduced or impaired.
For example, where snow has accumulated at the side of the highway, the object may not be readily or apparently visible to an operator of snow removal equipment traveling along the highway. In this case, the snow removal equipment may collide with the object, such as a culvert at the side of the highway, causing damage to both the snow removal equipment and the object. Accordingly, it is desirable to provide a marking device or flag to indicate the location of the object such that the operator can avoid any collision with the object.
In addition, as accidental collisions with the marking device may occur, it is further desirable that the marking device not readily or easily break or fail upon collision with the vehicle traveling on the highway.
As stated, although various marking devices have been developed, none have been found to be fully satisfactory. 
For instance, Swiss Patent No. 142477 published Sep. 30, 1930 by Amstutz shows a multi-component signaling device or marker incorporating a coiled spring. Specifically, a signaling post extends integrally up or vertically from a first end of the coiled spring, while a second end of the coiled spring acts as a bore for a tapered stake.
Similarly, French Patent No. 1,311,952 published Mar. 25, 1963 by Etablissements Vallette & Pavon also shows a multi-component signaling device incorporating a coiled spring. The coiled spring is provided with a vertically extending integral post at a first end. At a second end, the coiled spring tapers for one coil before vertically extending downwards for insertion into a bore on a stake for attachment to said stake via a nut.
In each of the above cases, the coil spring has an axis which extends parallel to the signaling post. As a result, in the event of any collision with the device, the signaling post and the coiled spring will tend to bend or twist about the axis of the coiled spring, which may increase the likelihood of breakage or failure of the device.
Further devices have been specifically developed for providing an audible signal to indicate the nearness of a vehicle to an object. Although these devices have a structure somewhat similar to the marking devices discussed above, they are unsuitable for use as highway marking devices.
For example, U.S. Pat. No. 2,141,844 issued Dec. 27, 1938 to Reznor relates to an obstruction detecting device that provides an audible warning to signal the approach to an object. For instance, the device may be applied to a vehicle to determine its proximity to a curb and in the case of a boat, to a pier. The device incorporates a coiled spring having an integral flexible reed-like arm at its first end and a clamp-like structure at its second end. The device is attached to a fixed part of the vehicle with the clamp-like structure. A hardened steel ball may be optionally attached to the end of the reed-like arm to impart the desired frequency to the vibratory system. Thus, contact between the flexible reed-like arm and an extraneous object will create a vibrational sound warning the driver of the proximity of the extraneous object. 
Further, U.S. Pat. No. 2,464,365 issued Mar. 15, 1949 to Aves also relates to a device, attachable to an automobile, for indicating the nearness of a curb or a similar obstruction during parking operations. Specifically, the device utilizes vibrations set up by contact between the device and the obstruction to mechanically produce an audible sound within the vehicle. The device includes an open coil spring integral with an antenna at a first end and attached to a clamp at a second end. The antenna preferably extends from a first end of the coil diagonally downwardly and outwardly at an acute angle to the longitudinal axis of the coil and at an acute angle to a perpendicular obstruction surface. The tip of the antenna is in the form of a small closed loop or ball adapted to engage the obstruction. The open coil spring is specifically provided to amplify the sound that is produced on impact with the obstruction and also to prevent the antenna from becoming permanently deformed when deflected by the obstruction.
Thus, in the event of collision with each of the signaling devices of Reznor and Aves, each of the devices is mounted with the vehicle in a manner to provide for the bending of the coiled spring and the arm or antenna about the axis of the coiled spring. For instance, the flexible coiled spring and the flexible, reed-like arm of Reznor are specifically mounted and configured to provide for bending about the coiled spring axis and thereby prevent injury to the device upon contact with the obstruction. Similarly, the open coil spring of Aves is specifically mounted and configured to bend about its-axis in order to prevent the antenna from becoming permanently deformed when deflected by the obstruction. In each case, bending or twisting of the arm or antenna and the coiled spring about the axis of the coiled spring may increase the likelihood of breakage or failure of the device with repeated use.
Thus, there remains a need in the industry for an improved highway marker device for marking the location of an object located adjacent to a highway. Preferably, the marker device provides enhanced or improved visibility of the object and is capable of resisting breakage or failure upon collision of a vehicle with the marker device.